The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
In general, a screw part including a bolt and a nut is a typical mechanical element for coupling two or more parts. The screw parts are used in various mechanical industrial fields including an automobile manufacturing field.
In particular, most of the work done in an assembly process of a completed vehicle production process in the automobile manufacturing field is engaging various parts to vehicle bodies using screw parts such as a bolt and a nut.
Furthermore, in a vehicle inspection line of the completed vehicle production process, wheel alignment of vehicles is inspected and adjusted. In such a wheel alignment process, an operator properly aligns tires by adjusting a toe, a camber, and a caster using a spanner and torque wrench.
For example, in the wheel alignment process, a stop nut of a tie rod assembly is loosened, an adjustment bolt is rotated to adjust a toe of the wheels, and the stop nut is subsequently tightened again to maintain the adjusted state of the toe.
In recent years, an operation of tightening or loosening screw parts such as a bolt and a nut has been performed using a robot in the wheel alignment process as described above. In order to perform a running operation of the screw parts using the robot, a robot gripper equipped with a gripper tool such as an electric bolt/nut runner is used at a front end of an arm of the robot in the related art.
However, in the related art, since gripper tools suitable for screw parts of various standards (e.g., sizes) are replaced to be used, a running operation time of the screw parts is increased due to a tool replacement time.
In addition, in the related art, we have discovered that when a running operation of the screw part is performed through a behavior of a robot in a state in which both sides of the screw part are gripped by a gripper tool having a planar group surface, the gripper tool is required to have higher holding power and torque as tightening torque of the screw part is increased, disadvantageously increasing the size and weight of the gripper tool.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.